1 /**
2 * collectd - src/write_kafka.c
3 * Copyright (C) 2014 Pierre-Yves Ritschard
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Pierre-Yves Ritschard <pyr at spootnik.org>
25 */
27 #include "collectd.h"
29 #include "plugin.h"
30 #include "common.h"
31 #include "utils_cmd_putval.h"
32 #include "utils_format_graphite.h"
33 #include "utils_format_json.h"
35 #include <stdint.h>
36 #include <librdkafka/rdkafka.h>
37 #include <errno.h>
39 struct kafka_topic_context {
40 #define KAFKA_FORMAT_JSON 0
41 #define KAFKA_FORMAT_COMMAND 1
42 #define KAFKA_FORMAT_GRAPHITE 2
43 uint8_t format;
44 unsigned int graphite_flags;
45 _Bool store_rates;
46 rd_kafka_topic_conf_t *conf;
47 rd_kafka_topic_t *topic;
48 rd_kafka_conf_t *kafka_conf;
49 rd_kafka_t *kafka;
50 char *key;
51 char *prefix;
52 char *postfix;
53 char escape_char;
54 char *topic_name;
55 pthread_mutex_t lock;
56 };
58 static int kafka_handle(struct kafka_topic_context *);
59 static int kafka_write(const data_set_t *, const value_list_t *, user_data_t *);
60 static int32_t kafka_partition(const rd_kafka_topic_t *, const void *, size_t,
61 int32_t, void *, void *);
63 #if defined HAVE_LIBRDKAFKA_LOGGER || defined HAVE_LIBRDKAFKA_LOG_CB
64 static void kafka_log(const rd_kafka_t *, int, const char *, const char *);
66 static void kafka_log(const rd_kafka_t *rkt, int level,
67 const char *fac, const char *msg)
68 {
69 plugin_log(level, "%s", msg);
70 }
71 #endif
73 static uint32_t kafka_hash(const char *keydata, size_t keylen)
74 {
75 uint32_t hash = 5381;
76 for (; keylen > 0; keylen--)
77 hash = ((hash << 5) + hash) + keydata[keylen - 1];
78 return hash;
79 }
81 static int32_t kafka_partition(const rd_kafka_topic_t *rkt,
82 const void *keydata, size_t keylen,
83 int32_t partition_cnt, void *p, void *m)
84 {
85 uint32_t key = kafka_hash(keydata, keylen);
86 uint32_t target = key % partition_cnt;
87 int32_t i = partition_cnt;
89 while (--i > 0 && !rd_kafka_topic_partition_available(rkt, target)) {
90 target = (target + 1) % partition_cnt;
91 }
92 return target;
93 }
95 static int kafka_handle(struct kafka_topic_context *ctx) /* {{{ */
96 {
97 char errbuf[1024];
98 rd_kafka_conf_t *conf;
99 rd_kafka_topic_conf_t *topic_conf;
101 if (ctx->kafka != NULL && ctx->topic != NULL)
102 return(0);
104 if (ctx->kafka == NULL) {
105 if ((conf = rd_kafka_conf_dup(ctx->kafka_conf)) == NULL) {
106 ERROR("write_kafka plugin: cannot duplicate kafka config");
107 return(1);
108 }
110 if ((ctx->kafka = rd_kafka_new(RD_KAFKA_PRODUCER, conf,
111 errbuf, sizeof(errbuf))) == NULL) {
112 ERROR("write_kafka plugin: cannot create kafka handle.");
113 return 1;
114 }
116 rd_kafka_conf_destroy(ctx->kafka_conf);
117 ctx->kafka_conf = NULL;
119 INFO ("write_kafka plugin: created KAFKA handle : %s", rd_kafka_name(ctx->kafka));
121 #if defined(HAVE_LIBRDKAFKA_LOGGER) && !defined(HAVE_LIBRDKAFKA_LOG_CB)
122 rd_kafka_set_logger(ctx->kafka, kafka_log);
123 #endif
124 }
126 if (ctx->topic == NULL ) {
127 if ((topic_conf = rd_kafka_topic_conf_dup(ctx->conf)) == NULL) {
128 ERROR("write_kafka plugin: cannot duplicate kafka topic config");
129 return 1;
130 }
132 if ((ctx->topic = rd_kafka_topic_new(ctx->kafka, ctx->topic_name,
133 topic_conf)) == NULL) {
134 ERROR("write_kafka plugin: cannot create topic : %s\n",
135 rd_kafka_err2str(rd_kafka_errno2err(errno)));
136 return errno;
137 }
139 rd_kafka_topic_conf_destroy(ctx->conf);
140 ctx->conf = NULL;
142 INFO ("write_kafka plugin: handle created for topic : %s", rd_kafka_topic_name(ctx->topic));
143 }
145 return(0);
147 } /* }}} int kafka_handle */
149 static int kafka_write(const data_set_t *ds, /* {{{ */
150 const value_list_t *vl,
151 user_data_t *ud)
152 {
153 int status = 0;
154 void *key;
155 size_t keylen = 0;
156 char buffer[8192];
157 size_t bfree = sizeof(buffer);
158 size_t bfill = 0;
159 size_t blen = 0;
160 struct kafka_topic_context *ctx = ud->data;
162 if ((ds == NULL) || (vl == NULL) || (ctx == NULL))
163 return EINVAL;
165 pthread_mutex_lock (&ctx->lock);
166 status = kafka_handle(ctx);
167 pthread_mutex_unlock (&ctx->lock);
168 if( status != 0 )
169 return status;
171 bzero(buffer, sizeof(buffer));
173 switch (ctx->format) {
174 case KAFKA_FORMAT_COMMAND:
175 status = create_putval(buffer, sizeof(buffer), ds, vl);
176 if (status != 0) {
177 ERROR("write_kafka plugin: create_putval failed with status %i.",
178 status);
179 return status;
180 }
181 blen = strlen(buffer);
182 break;
183 case KAFKA_FORMAT_JSON:
184 format_json_initialize(buffer, &bfill, &bfree);
185 format_json_value_list(buffer, &bfill, &bfree, ds, vl,
186 ctx->store_rates);
187 format_json_finalize(buffer, &bfill, &bfree);
188 blen = strlen(buffer);
189 break;
190 case KAFKA_FORMAT_GRAPHITE:
191 status = format_graphite(buffer, sizeof(buffer), ds, vl,
192 ctx->prefix, ctx->postfix, ctx->escape_char,
193 ctx->graphite_flags);
194 if (status != 0) {
195 ERROR("write_kafka plugin: format_graphite failed with status %i.",
196 status);
197 return status;
198 }
199 blen = strlen(buffer);
200 break;
201 default:
202 ERROR("write_kafka plugin: invalid format %i.", ctx->format);
203 return -1;
204 }
206 key = ctx->key;
207 if (key != NULL)
208 keylen = strlen (key);
209 else
210 keylen = 0;
212 rd_kafka_produce(ctx->topic, RD_KAFKA_PARTITION_UA,
213 RD_KAFKA_MSG_F_COPY, buffer, blen,
214 key, keylen, NULL);
216 return status;
217 } /* }}} int kafka_write */
219 static void kafka_topic_context_free(void *p) /* {{{ */
220 {
221 struct kafka_topic_context *ctx = p;
223 if (ctx == NULL)
224 return;
226 if (ctx->topic_name != NULL)
227 sfree(ctx->topic_name);
228 if (ctx->topic != NULL)
229 rd_kafka_topic_destroy(ctx->topic);
230 if (ctx->conf != NULL)
231 rd_kafka_topic_conf_destroy(ctx->conf);
232 if (ctx->kafka_conf != NULL)
233 rd_kafka_conf_destroy(ctx->kafka_conf);
234 if (ctx->kafka != NULL)
235 rd_kafka_destroy(ctx->kafka);
237 sfree(ctx);
238 } /* }}} void kafka_topic_context_free */
240 static void kafka_config_topic(rd_kafka_conf_t *conf, oconfig_item_t *ci) /* {{{ */
241 {
242 int status;
243 struct kafka_topic_context *tctx;
244 char *key = NULL;
245 char *val;
246 char callback_name[DATA_MAX_NAME_LEN];
247 char errbuf[1024];
248 oconfig_item_t *child;
249 rd_kafka_conf_res_t ret;
251 if ((tctx = calloc(1, sizeof (*tctx))) == NULL) {
252 ERROR ("write_kafka plugin: calloc failed.");
253 return;
254 }
256 tctx->escape_char = '.';
257 tctx->store_rates = 1;
258 tctx->format = KAFKA_FORMAT_JSON;
259 tctx->key = NULL;
261 if ((tctx->kafka_conf = rd_kafka_conf_dup(conf)) == NULL) {
262 sfree(tctx);
263 ERROR("write_kafka plugin: cannot allocate memory for kafka config");
264 return;
265 }
267 #ifdef HAVE_LIBRDKAFKA_LOG_CB
268 rd_kafka_conf_set_log_cb(tctx->kafka_conf, kafka_log);
269 #endif
271 if ((tctx->conf = rd_kafka_topic_conf_new()) == NULL) {
272 rd_kafka_conf_destroy(tctx->kafka_conf);
273 sfree(tctx);
274 ERROR ("write_kafka plugin: cannot create topic configuration.");
275 return;
276 }
278 if (ci->values_num != 1) {
279 WARNING("kafka topic name needed.");
280 goto errout;
281 }
283 if (ci->values[0].type != OCONFIG_TYPE_STRING) {
284 WARNING("kafka topic needs a string argument.");
285 goto errout;
286 }
288 if ((tctx->topic_name = strdup(ci->values[0].value.string)) == NULL) {
289 ERROR("write_kafka plugin: cannot copy topic name.");
290 goto errout;
291 }
293 for (int i = 0; i < ci->children_num; i++) {
294 /*
295 * The code here could be simplified but makes room
296 * for easy adding of new options later on.
297 */
298 child = &ci->children[i];
299 status = 0;
301 if (strcasecmp ("Property", child->key) == 0) {
302 if (child->values_num != 2) {
303 WARNING("kafka properties need both a key and a value.");
304 goto errout;
305 }
306 if (child->values[0].type != OCONFIG_TYPE_STRING ||
307 child->values[1].type != OCONFIG_TYPE_STRING) {
308 WARNING("kafka properties needs string arguments.");
309 goto errout;
310 }
311 key = child->values[0].value.string;
312 val = child->values[1].value.string;
313 ret = rd_kafka_topic_conf_set(tctx->conf,key, val,
314 errbuf, sizeof(errbuf));
315 if (ret != RD_KAFKA_CONF_OK) {
316 WARNING("cannot set kafka topic property %s to %s: %s.",
317 key, val, errbuf);
318 goto errout;
319 }
321 } else if (strcasecmp ("Key", child->key) == 0) {
322 cf_util_get_string (child, &tctx->key);
323 assert (tctx->key != NULL);
324 } else if (strcasecmp ("Format", child->key) == 0) {
325 status = cf_util_get_string(child, &key);
326 if (status != 0)
327 goto errout;
329 assert(key != NULL);
331 if (strcasecmp(key, "Command") == 0) {
332 tctx->format = KAFKA_FORMAT_COMMAND;
334 } else if (strcasecmp(key, "Graphite") == 0) {
335 tctx->format = KAFKA_FORMAT_GRAPHITE;
337 } else if (strcasecmp(key, "Json") == 0) {
338 tctx->format = KAFKA_FORMAT_JSON;
340 } else {
341 WARNING ("write_kafka plugin: Invalid format string: %s",
342 key);
343 }
345 sfree(key);
347 } else if (strcasecmp ("StoreRates", child->key) == 0) {
348 status = cf_util_get_boolean (child, &tctx->store_rates);
349 (void) cf_util_get_flag (child, &tctx->graphite_flags,
350 GRAPHITE_STORE_RATES);
352 } else if (strcasecmp ("GraphiteSeparateInstances", child->key) == 0) {
353 status = cf_util_get_flag (child, &tctx->graphite_flags,
354 GRAPHITE_SEPARATE_INSTANCES);
356 } else if (strcasecmp ("GraphiteAlwaysAppendDS", child->key) == 0) {
357 status = cf_util_get_flag (child, &tctx->graphite_flags,
358 GRAPHITE_ALWAYS_APPEND_DS);
360 } else if (strcasecmp ("GraphitePrefix", child->key) == 0) {
361 status = cf_util_get_string (child, &tctx->prefix);
362 } else if (strcasecmp ("GraphitePostfix", child->key) == 0) {
363 status = cf_util_get_string (child, &tctx->postfix);
364 } else if (strcasecmp ("GraphiteEscapeChar", child->key) == 0) {
365 char *tmp_buff = NULL;
366 status = cf_util_get_string (child, &tmp_buff);
367 if (strlen (tmp_buff) > 1)
368 WARNING ("write_kafka plugin: The option \"GraphiteEscapeChar\" handles "
369 "only one character. Others will be ignored.");
370 tctx->escape_char = tmp_buff[0];
371 sfree (tmp_buff);
372 } else {
373 WARNING ("write_kafka plugin: Invalid directive: %s.", child->key);
374 }
376 if (status != 0)
377 break;
378 }
380 rd_kafka_topic_conf_set_partitioner_cb(tctx->conf, kafka_partition);
381 rd_kafka_topic_conf_set_opaque(tctx->conf, tctx);
383 ssnprintf(callback_name, sizeof(callback_name),
384 "write_kafka/%s", tctx->topic_name);
386 user_data_t ud = {
387 .data = tctx,
388 .free_func = kafka_topic_context_free
389 };
391 status = plugin_register_write (callback_name, kafka_write, &ud);
392 if (status != 0) {
393 WARNING ("write_kafka plugin: plugin_register_write (\"%s\") "
394 "failed with status %i.",
395 callback_name, status);
396 goto errout;
397 }
399 pthread_mutex_init (&tctx->lock, /* attr = */ NULL);
401 return;
402 errout:
403 if (tctx->topic_name != NULL)
404 free(tctx->topic_name);
405 if (tctx->conf != NULL)
406 rd_kafka_topic_conf_destroy(tctx->conf);
407 if (tctx->kafka_conf != NULL)
408 rd_kafka_conf_destroy(tctx->kafka_conf);
409 sfree(tctx);
410 } /* }}} int kafka_config_topic */
412 static int kafka_config(oconfig_item_t *ci) /* {{{ */
413 {
414 oconfig_item_t *child;
415 rd_kafka_conf_t *conf;
416 rd_kafka_conf_res_t ret;
417 char errbuf[1024];
419 if ((conf = rd_kafka_conf_new()) == NULL) {
420 WARNING("cannot allocate kafka configuration.");
421 return -1;
422 }
423 for (int i = 0; i < ci->children_num; i++) {
424 child = &ci->children[i];
426 if (strcasecmp("Topic", child->key) == 0) {
427 kafka_config_topic (conf, child);
428 } else if (strcasecmp(child->key, "Property") == 0) {
429 char *key = NULL;
430 char *val = NULL;
432 if (child->values_num != 2) {
433 WARNING("kafka properties need both a key and a value.");
434 goto errout;
435 }
436 if (child->values[0].type != OCONFIG_TYPE_STRING ||
437 child->values[1].type != OCONFIG_TYPE_STRING) {
438 WARNING("kafka properties needs string arguments.");
439 goto errout;
440 }
441 if ((key = strdup(child->values[0].value.string)) == NULL) {
442 WARNING("cannot allocate memory for attribute key.");
443 goto errout;
444 }
445 if ((val = strdup(child->values[1].value.string)) == NULL) {
446 WARNING("cannot allocate memory for attribute value.");
447 sfree(key);
448 goto errout;
449 }
450 ret = rd_kafka_conf_set(conf, key, val, errbuf, sizeof(errbuf));
451 if (ret != RD_KAFKA_CONF_OK) {
452 WARNING("cannot set kafka property %s to %s: %s",
453 key, val, errbuf);
454 sfree(key);
455 sfree(val);
456 goto errout;
457 }
458 sfree(key);
459 sfree(val);
460 } else {
461 WARNING ("write_kafka plugin: Ignoring unknown "
462 "configuration option \"%s\" at top level.",
463 child->key);
464 }
465 }
466 if (conf != NULL)
467 rd_kafka_conf_destroy(conf);
468 return (0);
469 errout:
470 if (conf != NULL)
471 rd_kafka_conf_destroy(conf);
472 return -1;
473 } /* }}} int kafka_config */
475 void module_register(void)
476 {
477 plugin_register_complex_config ("write_kafka", kafka_config);
478 }